The 59-year-old actress said in the Nov. 5 issue of People that she's grateful to have survived a secret, 10-year addiction to opiates that began in the late 1980s.

"I was ahead of the curve of the opiate epidemic," she told the magazine. "I had a 10-year run, stealing, conniving. No one knew. No one."

Curtis' addiction started after she was prescribed opiates in 1989 after undergoing minor plastic surgery. Her sister Kelly Curtis learned of her habit in 1998, and she attended her first recovery meeting the next year.

"Getting sober remains my single greatest accomplishment ... bigger than my husband, bigger than both of my children and bigger than any work, success, failure. Anything," the star said.

Curtis shared similar sentiments in an interview with USA Today published last week.

"As soon as I got sober, which is 20 years coming up in February, everything changed. Because it was a big, big acknowledgement that I could not do all of the things I was trying to do," the actress and mom said.

"I have made shifts along the way," she said of getting sober. "That's the single greatest accomplishment of my life."

Curtis is also celebrating the success of the new Halloween movie, which opened in theaters last week. The film was No. 1 at the North American box office over the weekend, earning $77.5 million.